Arrythmia Flashcards
What is ectopic beats?
-extra or skipped heartbeats
-they are common
What is the tx for ectopic beats?
Beta blockers
What is atrial fibrillation?
-irregular and often abnormally fast heart rate
-100+ beats per min
What can AF lead to?
Stroke
->blood may not be fully ejected so can cause clot
whatare the 2 types of AF tx?
Ventricular rate control or sinus rhythm control
What is ventricular rate control?
Using medications
What is sinus rhythm control?
Using cardioversion
What do you do if pt presents with life-threatening haemodynamic instablilty?
Emergency electrical cardioversion w/o delaying to achieve anticoagulation
What do you do if pt presents w/o life-threatening haemodynamic instablilty within < 48hr
Rate or rhythm control
What do you do if pt presents w/o life-threatening haemodynamic instablilty within > 48hr
Rate control
What is pharmacological cardioversion?
Flecainide or amiodarone
What should be started and ruled with electrical cardioversion?
start IV anticoagulation + rule out left atrial thrombus
What is 1st line of AF maintenance?
-rate control monotherapy
-standard BBlocker (x sotalol) OR RL CCB (Diltiazem or verapamil) or digoxin (predominantly sedentary pt with non-paroxysmal AF)
what is 2nd line of AF maintenance?
rate control with dual therapy (bblocker + digoxin or ditiliazem)
what is 3rd line of AF maintenance?
-rhythm control
-if >48hr risk of clotting so electrical cardioversion
-Pt needs to be anticoagulated for at least 3 weeks and given oral anticoagulation for 4 wks after
What drugs are used for post cardioversion tx?
how long to ant
SPAF
-sotalol
-propafenone
-amiodarone ( start 4wk before and continue for 12MT)
-flecainide
What is paroxysmal AF?
Intermittent episodes of AF that terminate within seven days either spontaneously or with intervention.
How to tx paroxysmal AF?
1) Standard beta blockers
2) SPAF
tx of episodes of paroxysmal AF?
pill in pocket
flecainide/propafenone PRN
How does stroke prevention work?
-Assess risk of stroke + need for thromboprphylaxis (warfarin) using CHA2DSC2-VASc
- Not needed if men = 0 women =1
what is CHA2DSC2-VASc?
C = congestive heart failure - 1
H = hypertension - 1
A2 = age 75+ - 2
D = diabetes - 1
S2 = stroke/TIA - 2
V = vascular disease - 1
A = age 65-74 - 1
Sc = sex female - 1
+ more effective
what are the two tx of atrial flutter?
-rhythm or rate control
-more effective with cardioversion
which meds are used to tx atrial flutter
Bblockers or RL CCB
+symptoms
what is atrial flutter?
-abnormal heart rhythm (arrhythmia) which causes the upper chambers of your heart (atria) to beat too quickly
-symptoms = palpitations and feeling light-headed
How is rhythm control used in atrial flutter?
1) Direct current cardioversion
2) Pharmacological cardioversion
3) catheter ablation (recurrent tx)
What do you do if atrial flutter has lasted >48hr?
anticoagulation for 3wk
What is paroxysmal supraventricular tachycardia?
-due to development of short circuit rhythm in the upper chamber of the heart
-results in a regular but rapid heartbeat that starts and stops abruptly
-normally tx not needed
What is the tx for paroxysmal supraventricular tachycardia?
should terminate spontaneously on its own
1) reflux vagal stimulation
2) IV adenosine
3) IV verapamil
What is the tx for reccurent paroxysmal supraventricular tachycardia?
recurrent - catheter ablation
What is given to prevent future paroxysmal supraventricular tachycardia?
bblockers or RL CcB
What is ventricular tachycardia?
-abnormal heart rhythm or arrhythmia
-occurs when the lower chamber of the heart beats too fast to pump and the body doesn’t receive enough oxygenated blood
How do you tx pulseless ventricular tachycardia or ventricular fibrillation?
resuscitation
How do you tx unstable sustained ventricular tachycardia?
-direct current cardioversion or IV amiodarone
-repeat current cardioversion of others x work
How do you tx stable ventricular tachycardia?
1) IV amiodarone then direct current cardioversion
2) if x sustained bblocker
What is the maintenance therapy for pt who are at high risk of cardiac arrest?
Pharm + nonpharm tx
1) implantable cardioverter defibrillator
2) + bblocker or amiodarone (in combination with bblocker)
What is QT prolongation?
-extended interval between the heart contracting and relaxing
-increases risk of experiencing abnormal heart rhythms and sudden cardiac arrest
-can be present from birth, or it may develop later in life
-usually self-limiting** but can be recurrent
-can lead to impaired consciousness if not controlled VF to DEATH
What causes QT prolongation?
-drug-induced (amiodarone, sotalol, macrolides, SSRI, TCA, antifungals, haloperidol)
-hypokalaemia
-severe bradycardia
What is tx for QT prolongation?
-IV magnesium sulphate
-Blocker x sotalol
-Consider atrial/ventricular pacing
What is anti-arrhythmic drugs classified into?
Supraventricular arrythmias
ventricular arrythmias or both
What is the electrical classification of anti-arrhythmic drugs?
less clinical
1) membrane stabilising drugs flecainide/lidocaine
2) bblockers
3) amiodarone, sotalol
4) CCB verapamil, diltiazem
What is the dose of amiodarone ?
200mg TDS 7DY* 200mg BD 7DY* 200mg OD DIR
When do you avoid amiodarone?
in bradycardia and heartblock
What is the S/E of amiodarone?
- corneal microdeposits (reversible if tx stopped)
- thyroid disorders - hyper/hypo due to iodine
- photosensitivity - avoid sunlight
- hepatoxicity - liver disease
- pulmonary toxicity - SoB, cough
- vision impaired - blurry
Interactions of amiodarone?
- drugs that cause hyperkalaemia
- drugs that cause QT prolongation
- CYP450 enzyme inhibitors/inducers
- drugs that cause bradycardia
Monitoring for amiodarone?
Including IV route
- Thyroid functions before * 6MT
- LFT “ “
-
Chest x-ray before tx
-annual eye exams - IV route : ECG + liver transaminase
Which drugs need to monitored after stopping amiodarone?
for heartblock
Sofosburvir, daciatosuvir, simeprevir, sofosbuvir, lediapruvir
What is maintenance dose for digoxin for AF?
125-250mcg
Different bioavailabilites for diff formulations
what is therapeutic range for digoxin
0.7 to 2.0ng/ml
What is the toxicity range for digoxin
1.5 - 3.0ng/ml
What are the signs of toxicity for digoxin?
SICK + SLOW
- SA/AV block + bradycardia
- diarrhoea + vomiting
- dizziness, confusion, depression
- blurred/yellow vision
Monitoring for digoxin?
-serum electrolytes + renal function
-take blood samples 6-12hr after each dose
Digoxin interactions?
- bblockers - inc risk of AV block + inc plasma conc
- tricyclic antidepressants - induce arrythmias
- drugs that cause hypokalaemia (inc digoxin toxicity)
- cyp450 inducers (dec) + inhibtors (inc)
